Bag filling machines



NOV. 6, E M LAU BAG FILLING MACHINES 2 Sheets-Sheet 1 Filed' March 23,1959 ,z w Z; W

Nov. 6, 1962 E. M. LAU 3,062,307

BAG FILLING MACHINES Filed March 23, 1959 2 Sheets-Sheet 2 .772 de: 7aZza 7": gg f v frzdlrz M ,Za

United States Patent Oil-ice 3,06Z,307 Patented Nv. 6, 1982 3,062,307BAG FILLING MACHINES Erwin M. Lan, Dalton, Ill., assignor to BlackProducts Co., Chicago, Ill., a corporation of Illinois Filed Mar. 23,1959, Ser. No. 801,143 9 Claims. (Cl. 177-118) This invention relates toimprovements in bag filling machines of the automatic cut-off type.

In machines of this type, the bag is suspended from the filling spout.The filling spout is mounted on a frame which bears on the beam of scalemechanism. When a predetermined amount of material has been fed into thebag, the movement of the beam cuts off the filling operation.

An object of this invention is to provide a bag filling machine in whichthe beam axis is parallel to the spout aXis so that the position of thebag on the spout will not vary the length of the lever arm, and henceaffect the accuracy of the scale mechanism.

Another object is to provide a spout assembly in the form of -asuspended frame, thus reducing the number of bearing points required.and providing a simplified construction without sacrifice ofsensitivity.

A still further object is to provide a beam construction which does notinterfere with the location of the various parts of the feedingmechanism.

Still another object is to provide an improved bag filling machine whichembodies a minimum number of bearing points, thus reducng the frictionincident to operation and providing greater sensitivity.

The invention is shown with respect to feeding mechanism of thefluidizing type, such as shown in my copending application, Serial No.608,760 filed September 10, 1956, now Patent No. 2,936,994, although itwill be understood that this type of feeding mechanism is shown by wayof example only, and the invention is equally applicable to other typesof feeding mechanism. i

Other objects, features, and advantages will become apparent as thedescription proceeds.

With reference now to the drawings in which like reference numeralsdesignate like parts:

FIG. 1 is a front elevation of a preferrcd embodiment of my invention;

PIG. 2 is la right side elevation thereof;

FIG. 3 is a left side elevation thereof;

FIG. 4 is a plan view taken along line 4- 4 of PIG. 2;

FIG. 5 is a Vertical section through the fulcrum;

FIG. 6 is an isometric view of the beam; and

FIG. 7 is a view similar to FIG. 5 showing the bearing means.

With reference now to FIGS. l to 4, the bag filling machine comprises abed plate 10 and suitable supporting framework 19. Mounted on the bedplate are feeding mechanism designated generally by the referencenumeral 11 and scale mechanism which includes a beam 25, and a suspendedspout assembly 34.

The feeding mechanism 11 shown herein by way of example comprises aconditioning chamber 12 having as its bottom wall a diffusing pad 13. Afiexible flanged tube 14, such as a rubber tube, extends forwardly froman opening in the front wall of the conditioning chamber 12 andcommunicates with the rear end of a spout 15 on which the bag is to besuspended. The flanged tube 14 is supported at an intermediate point bya Vertical plate 17 which is mounted on the bed plate 10.

Material is caused to fiow from the conditioning chamber 12 through thefianged tube14 and into a bag when the diffuser pad 13 is energized bymeans of an air supply 18. w

Cut-off means to discontinue the feeding operation-are provided in theform of a pinch valve 16 for the tube 14,

and a valve 42 for the air supply 18. The feeding mechanism is describedin greater detail in my aforesaid copending application to whichreference is hereby made.

Scale mechanism is provided to actuate the cut-off means when the weightof the bag contents reaches a predetermined amount. The scale mechanismcomprises a beam 25 which is mounted on Vertical fulcrum posts 20 and 21in such a manner that the fulcrum axis of the beam is parallel to theaxis of the spout 15.

The fulcrum posts 20 and 21 project upwardly from the bed plate 10 towhich they are suitably secured and -are provided at their upper endswith suitable fulcrum means, such as the edge disks 23. The disk 23 isshown in detail in FIG. 5, and is mounted in a slot 22 in each post bymeans of an axle 24, the ends of the aXle being received in suitablebores formed in the post.

The beam 25, as shown in FIG. 6, comprises front and rear invertedU-shaped members 26 and 27 which are connected by a longitudinallyextending side bar 28. A hardened fulcrum pad 29 is secured to each ofthe members 26 and 27 and is provided with a notch 30 into which thefulcrum edge disk 23 extends. As more fully pointed out in the aforesaidcopending application, the notch 30 is cut on a radius which is somewhatgreater than the radius of the edge disk 23, this arrangement providinga very Sensitive and substantially frictionless bearing for the beam.

The front member 26 of the beam also includes a slotted support 31 whichaccommodates an edge disk 32, mounted on an axle 33.

A spout assembly 34 is suspended from the edge disk 32 as shown in FIGS.1 and 3. The spout assembly 34 includes the spout 15, a mounting plate35 therefor, a support pad 36 which extends rearwardly from the upperportion of the mounting plate 35, and a tail 37. A suitable. notch 38similar to the notch 30 but of greater angular length of are is formedin the lower surface of the support pad 36 and cooperates with the edgedisk 32, as shown in FIG. 7.

Thus the medial plane of the suspended spout assembly 34 will tend toremain Vertical during the rocking of the beam 25, and the lever arm,which constitutes the horizontal distance between the fulcrum points 23and 32, will be maintained constant at all times. According to thisarrangement, the location of the bag upon the spout 15 will not affectthe lever arm.

An actuating arm 40 is secured to the rear member 27 of the beam andengages the plunger of a microswitch 41 to lstop the feeding operationwhen the beam is rotated in the counterclockwise direction, as viewed inFIGS.

1 and 6, the microswitch being suitably connected to the pinch valve 16and to the cut-off valve 42 by means not shown herein.

The beam is loaded by applying suitable balance weights 49 to a weightrod 43 which, as shown in FIG. l, depends from the side bar 28 from thebeam. The weight rod may be rigidly secured to the side bar 28 'asshown, or it may be linked thereto. Suitable stop means may be providedto limit the throw of the beam, and in the case of the rigidly connectedweight rod shown, the stop means may be in the form of a yoke 44 whichis suitably mounted -on the framework and which engagesl the lower endof the weight rod.

In order to prevent pivoting of :the spout assembly 34 labout thefulcrum32, suitable 'strut means, such as a spacer point 45, is provided at thelower end of the tail' 37. By locating the spacer point at the lowerportion of the tail 37, the lever arm with respect to the point ofsupport 32'is sufficiently great as to develop only a comparamaaac?tively small reaction force. Thus the load on the spacer point 45 isreduced and hence the frictional wear.

More specifically, the Vertical distance between the point of support 32and the spacer point 45 may be', for example, three times the horizontaldistance between the center of gravity -of the bag and the point ofsupport. Therefore, the reaction force between the spacer point 45 andthe tail 37 will be only one third of the bag weight, or about 33 poundsin the case of a one hundred pound bag. By thus reducing the reactionforce and the friction, sensitivity is correspondingly increased.

Furtherrnore, the suspended spout assembly construction requires the useof only one spacer point as `contrasted with the eight spacer pointswhich are |required in the floating frame type of construction shown inmy earlier Patent No. 2,733,040", dated January 31, 1956. Thus, theproblem of parallel alignment of a plurality of spacer points iseliminated, and greater sensitivity is obtained.

The spacer point 45 is located between notched plates 46 and 47, oneplate being mounted on the tail 37, and the other being connected to asuitable| cross member of the framework.

The suspended spout assembly 34 is confined against inadvertent removal'by means of a yoke 48 which loosely surrounds a portion of the tail 37.However, the yoke 48 should have sufiicient lclearance to permit thespout assembly to move forwardly and upwardly to a slight extent fromthe centered position. The yoke 48 may be removably secured to a plate49 which depends from the bed plate 10.

The means by which the spout assembly is suspended from the beam, namelythe edge disk 32 and the notched support pad 36, in addition to providnga very sensitive bearing or fulcrum point, also permits the parts toseek a position of equilibrium in which the spout assembly movesforwardly and clmbs slightly on the edge disk 32, 'as shown in FIG. 7.This is due to the fact that there is also a horizontal reaction forcebetween the edge disk 32 and the support pad 36 which corresponds inmagnitude `to 'the reaction force of the spacer point 45.

To the extent that the tangent of the line of contact between the edgedisk 32 and notch departs from the horizontal, this climbing tends toreduce slightly the sensitivity of the bearing point, but the extent ofclimbing is minimized 'by locating the spacer point 45 so as to reducethe reaction force as pointed out above. However, the horizontalreaction force has no effect on the lever arm of the beam because it isparallel to the fulcrum axis.

Thus it will be seen that the edge disk 32 provides bearing means inwhich sensitivity of action in one direction is not affected by ahorizontal reaction force which is eXerted in a direction perpendicularthereto.

In operation, the weight rod 43 is first loaded in accordance with theamount of material to be packed in the bag. Then the bag is slipped overthe spout and the fillng operation is initiated by causing the pinchvalve 16 to be opened and by supplying air to the diifusing pad 13. Atthis time the weight rod 43 engages the left arm of the yoke 44 as shownin FIG. 1. Then, when the desired amount of material has been fed intothe bag the beam will be tripped causing the beam to be rotated in thecounterclockwise direction and Operating the microswitch 41 to actuatethe cut-off means 16-42.

By providng a beam in which the longitudinal member 28 is disposed atone side, interference with the feeding mechanism 11, and in particularwith the conditioning 'Chamber 12, is avoided, thus providng a morecompact arrangement and permitting application of the invention ltovarious types of feeding mechanisms.

The invention is equally applicable to other types of bag fillngmachines, such as an auger type of machine, the uidizing type beingshown herein for purposes of llustration only.

Although a preferred lembodiment of this invention has been shown and-described herein, it will be understood that various modifications andchanges may be made in |the construction shown without departing fromthe spirit of this invention as pointed out in the appended claims.

I claim:

1. A bag fillng machine comprising material feeding mechanism and scalemechanism, said scale mechanism including a beam, said beam comprisingspaced front and rear beam arms and a longitudinal connecting member, aspout assembly supported by said beam forwardly of said front beam armand including a bag supporting spout communicating with said feedingmechanism, means for mounting said beam on a fulcrum axis which isparallel to the axis of said spout whereby the longitudinal position ofa bag which is suspended from said spout will not aifect the lever armof the force exerted by said bag upon said beam, said feeding mechanismincluding cut-off means for discontinuing the feeding operation, meansactuated by the movement of said beam when the material fed into saidbag reaches a predetermined weight for actuating said cut-off means,said beam mounting means comprising two spaced aligned fulcrum membersengaging said two beam arms, and balance weight means connected to saidbeam at a point rearwardly of said front beam arm.

2. A bag filling machine comprising material feeding mechanism and scalemechanism, said scale mechanism including a beam, said beam comprisingspaced front and rear beam arms and a longitudinal connecting member, aspout assembly having a spout and a supporting frame therefor, means forsuspending said spout assembly from said beam, fulcrum means formounting said beam on a fulcrum aXis which is parallel to the axis ofsaid spout whereby the longitudinal position of a bag which is suspendedfrom said spout will not affect the lever arm of the force exerted bysaid bag upon said beam, said feeding mechanism being in communicationwith said spout so that material may be fed through said spout and intoa bag which is suspended therefrom, and said feeding mechanism includingcut-off means for discontinuing the feeding operation, means actuated bythe movement of said beam when the material fed into said bag reaches apredetermined weight for actuating said cut-off means, and balanceweight means connected to said beam at a point rearwardly of said frontbeam arm.

3. A bag fillng machine as claimed in claim 2 in which said beammounting means comprises a pair of aligned edge disks and arcuatenotched fulcrum pads for supporting said beam at said front and rearbeam arms, said balance weight means being located between said frontand rear beam arms but being offset on the opposite side of said fulcrumaxis from said spout assembly, and in which said spout assemblysuspending means comprises an edge disk and an arcuate notched supportpad cooperating therewith.

4. A bag fillng machine as claimed in claim 2 in which said means forsuspending said spout assembly from said beam comprises bearing meansfor taking up a horizontal reaction force imposed on said spout assemblyby the weight of a bag suspended thereby, and for providng a knife edgetype of bearing which provides sensitivity of movement of said spoutassembly in a plane perpendicular to said beam axis while said reactionforce is present.

5. In a bag filling machine of the automatic cut-off type, thecombination of a spout from which a bag may be suspended, a beam mountedfor movement about a fulcrum axis which is parallel to the aXis of saidspout, and means for supporting said spout from said beam, said supportmeans comprising a support plate, bearing means for supporting saidsupport plate from said beam so that said support plate may hang freelyin a plane perpendicular to asid fulcrum axis, a tail for said supportplate, and strut means engaging the lower portion of said tail in orderto provide a reaction point, the lever arm of said reaction point withrespect to said bearing means being substantially greater than the leverarm of a spout suspended bag with respect to said bearing means so thatthe force exerted on said strut is substantially less than the forceexerted by the weight of said bag on said spout, thereby reducingfrictional wear of said strut means, and balance weight means connectedto said beam at a point which is offset in a direction parallel to saidfulcrum axis from said spout suspended bag.

6. A bag filling machine as claimed in claim 5 in which said bearingmeans comprises an edge disk carried by said beam and an arcuatelynotched bearing pad cooperating therewith and carried by said supportplate, the edge of said edge disk being parallel to said fulcrum axiswhereby said bearing means can accommodate a horizontal reaction forcewithout substantially impairing the sensitivity thereof with respect tomovement in said perpendicular pl-ane.

7. In a bag filling machine of the automatic cut-off type thecombination of a bed plate, feeding mechanism located on said bed plate,a bag supporting spout communicating with said feeding mechanism,fulcrum means mounted on said bed plate and providing a fulcrum axiswhich is parallel to said spout, beam means mounted on said fulcrummeans, said beam means comprising front and rear inverted U-shapedmembers and a longitudinal member connecting said front and rearmembers, said longitudinal member being located on the opposite side ofsaid fulcrum aXis from said feeding mechanism so as to avoidinterference between said beam means and said feeding mechanism, aportion of said feeding mechanism extending into the space between saidfront and rear beam members, said spout being supported by said beammeans at a point forwardly of said front member, and a balanceweightconnected to said beam means at a point rearwardly of said front member.

8. A bag filling machine as claimed in claim 7 in which said fulcrummeans comprises a pair of spaced posts mounted on and projected upwardlyfrom said bed plate and extending into the spaces defined by theinverted U-shape of said front and rear members respectively, the upperend of each post being notched, an edge disk rotatably mounted in eachnotch, and an arcuately notched fulcrurn pad carried on the undersurface of the connecting portion of each of said U-shaped members forcooperation with said edge disk.

9. In a bag filling machine of the automatic cut-off type, thecombination of a bag supporting spout, a beam mounted for movement abouta fulcrum axis which is parallel to the axis of said spout, said beamcomprising spaced front and rear beam arms and a longitudinal connectingmember, a suspended spout assembly for supporting said spout from saidbeam, bearing means for suspending said spout assembly from said beamand providing an upper reaction point for said spout assembly meansproviding a lower reaction point for said spout assembly, the Verticaldistance between said upper and lower reaction points beingsubstantially greater than the horizontal distance between the outer endof said spout and said bearing means, and balance weight means connectedto said beam at a point rearwardly of said front beam arm.

References Cited in the file of this patent UNITED STATES PATENTS1,578,748 Nelson Mar. 30, 1926 2,408,225 Peterson Sept. 24, 1946 2,723,lHess Nov. 8, 1955

